1. Field of the Invention
This invention relates to an apparatus for thermotherapy with an inserting part inserted in a vital lumen such as, for example, a blood vessel, an urethra, or an abdominal cavity, or with an applying part surgically pressed against a vital tissue, or with an applying part pressed against a body surface and then irradiating a relevant vital tissue such as, for example, a prostate gland tissue with the energy from a laser beam, a microwave, a radio frequency, or an ultrasound which is released from an emitting part thereof disposed in the inserting part or the applying part.
2. Description of the Related Art
A known apparatus for thermotherapy of a given lesion site uses a long and slender inserting part adapted to be inserted into the living body via a lumen or a small incision artificially formed in the skin and irradiates tissue (e.g., prostate gland tissue) with energy, thereby eliminating the lesion site by inducing degeneration, necrosis, solidification, cauterization, or transpiration of the affected tissue.
This apparatus for thermotherapy is generally adapted to project the energy directly on the site of lesion located on the surface layer of the vital tissue or in the proximity thereof. The technique which, as in the thermotherapy of the prostate gland, irradiates the deep part of a vital tissue with the energy for the purpose of curing the site of lesion located in the deep part of a vital tissue, namely the site of lesion in the deep part, has been also known. Further, another known apparatus for thermotherapy has a heat source emitting part disposed on the leading terminal side of the inserting part with a refrigerant for cooling the neighboring tissue. According to this apparatus, the deep part of the vital tissue is concentrically heated while the neighborhood of the surface layer of the vital tissue in proximity to the emitting terminal of the inserting part is kept cooled and protected against possible heat injury.
In a conventional apparatus for thermotherapy, the therapeutic conditions are set by the following method. To be specific, the operator himself makes a judgment from his own experience in the selection of therapeutic conditions including, for example, the power of a heat source such as the laser, the duration of exposure to the heat source, the temperature of the refrigerant, and the flow volume of the refrigerant to be circulated. The operator then imparts these conditions to the apparatus.
In addition, a method which sets such therapeutic conditions as the power of a heat source by imparting to the apparatus the target temperature of a vital tissue of the lesion site (or the proximity of the lesion site) to which the long and slender inserting part thereof is inserted has been known (the official gazette of JP-A-07-95,987).
In the apparatus for thermotherapy mentioned above, however, it is generally difficult to estimate the approximate range of heating on the basis of the preset levels of the individual therapeutic conditions. The difficulty encountered in this estimation of the range of heating grows proportionally as the number of therapeutic conditions to be set increases.
The method which relies on the operator""s judgment to set the therapeutic conditions, therefore, not only complicates the operation of imparting the therapeutic conditions but also entails the possibility of setting erroneous therapeutic conditions. Consequently, this method has the risk that the energy of heating will be so excessive as to inflict damage on the normal tissue in the proximity of the lesion site or that energy of heating will be so deficient as to prevent attainment of a sufficient therapeutic effect.
The method which relies upon imparting the target temperature of the vital tissue at the site of lesion or in the proximity of the site of lesion has the problem that the information concerning the size, position, and length of the site of lesion is not reflected in the therapeutic conditions to be set. Thus, when the energy of heating and the cooling are both excessive, for example, and even when the prescribed point in the site of lesion is allowed to reach the target temperature, the possibility arises that the range of heating will be so wide that the part to be heated will not be limited to the site of lesion but will be extended to the normal tissue in the proximity of the site of lesion and consequently the normal tissue may be damaged. When the energy of heating and the cooling are both insufficient, for example, and even when the prescribed point in the site of lesion is allowed to reach the target temperature, the possibility arises that the range of heating will be too narrow to attain the effect of therapy sufficiently. The possibility also arises that the part to be heated will deviate from the site of lesion and the effect of therapy aimed at will not be obtained satisfactorily.
One object of the invention is to provide an apparatus for thermotherapy which, depending on the morbid state of a patient, allows therapeutic conditions for effectively heating exclusively a given site of lesion to be set accurately and easily, and meanwhile prevents the normal tissue in the proximity of the site of lesion from sustaining damage.
One aspect of this invention concerns an apparatus for effecting thermotherapy of the prostate gland by exposing the affected vital tissue to an energy, the therapeutic conditions for the thermotherapy of the prostate gland being set based on input information including the data of diagnosis of the prostate gland.
Another aspect of this invention concerns an apparatus for effecting thermotherapy of the prostate gland by exposing the affected vital tissue to an energy, the therapeutic conditions for the thermotherapy of the prostate gland being set based on an input information including data for specifying the size of the prostate gland.
Still another aspect of this invention concerns an apparatus for effecting thermotherapy of the prostate gland by exposing the affected vital tissue to an energy, which apparatus comprises an input part for imparting to the apparatus input information including the data for specifying the size of the prostate gland and a control part for setting the therapeutic conditions for effecting the thermotherapy of the prostate gland on the basis of an input information imparted by the input part.
When the apparatus is constructed as described above, proper therapeutic conditions are automatically set by simply imparting to the apparatus input information including data for specifying the size of the prostate gland. The operation for the impartation of the input information is facilitated because the operator does not need to incur the trouble of judging from his own experience numerous therapeutic conditions to be set and imparting them one by one. Moreover, this construction can prevent the operator from setting erroneous therapeutic conditions. Depending on the morbid state of each patient, therefore, the apparatus is able to accurately and easily heat the site of lesion exclusively while preventing the normal tissue in proximity to the site of lesion from sustaining damage.
Another aspect of this invention concerns an apparatus for effecting thermotherapy by exposing the affected vital tissue to an energy, with the therapeutic conditions for the thermotherapy being set based on an input information including the position of a target heating site.
Still another aspect of this invention concerns an apparatus for effecting thermotherapy by exposing the affected vital tissue to an energy, which apparatus comprises an input part for imparting to the apparatus input information including data specifying the position of a target heating site and a control part for setting the therapeutic conditions for effecting the thermotherapy.
When the apparatus is constructed as described above, since proper therapeutic conditions are automatically set by simply imparting to the apparatus input information including position information concerning a target site which is a target site of heating, the operation for the impartation of the input information is facilitated because the operator does not need to incur the trouble of judging from his own experience numerous therapeutic conditions to be set and imparting them one by one. Moreover, this construction can prevent the operator from setting erroneous therapeutic conditions. Depending on the morbid state of each patient, therefore, the apparatus is enabled to heat accurately and easily the site of lesion exclusively and meanwhile prevent the normal tissue in the proximity of the site of lesion from sustaining damage.
The other objects, features, and characteristics of this invention will be apparent from the following description and the preferred embodiments illustrated in the drawings annexed hereto.